url-mode: store absolute row numbers in start/end coordinates

This allows us to update the jump label positions when the viewport
changes.

This in turn allows us to stay in URL mode while the user is using the
mouse to scroll in the scrollback history.

Scrolling with the keyboard is currently not possible, since input
handling in URL mode does not recognize “regular” key bindings. We
_could_ add scrollback up/down bindings to URL mode too, but lets not,
for the time being.

(Note: an alternative to this patch is to disallow mouse scrolling
too. Then we could have kept the URL start/end as viewport local
coordinates).

commands.c

@@ -83,6 +83,7 @@ cmd_scrollback_up(struct terminal *term, int rows)
     } else
         term_damage_view(term);
 
+    render_refresh_urls(term);
     render_refresh(term);
 }
 
@@ -157,5 +158,6 @@ cmd_scrollback_down(struct terminal *term, int rows)
     } else
         term_damage_view(term);
 
+    render_refresh_urls(term);
     render_refresh(term);
 }

render.c

@@ -2524,6 +2524,15 @@ render_urls(struct terminal *term)
     struct wl_window *win = term->window;
     xassert(tll_length(win->urls) > 0);
 
+    /* Calculate view start, counted from the *current* scrollback start */
+    const int scrollback_end
+        = (term->grid->offset + term->rows) & (term->grid->num_rows - 1);
+    const int view_start
+        = (term->grid->view
+           - scrollback_end
+           + term->grid->num_rows) & (term->grid->num_rows - 1);
+    const int view_end = view_start + term->rows - 1;
+
     tll_foreach(win->urls, it) {
         const struct url *url = it->item.url;
         const wchar_t *text = url->text;
@@ -2535,6 +2544,18 @@ render_urls(struct terminal *term)
         if (surf == NULL || sub_surf == NULL)
             continue;
 
+        const struct coord *pos = &url->start;
+        const int _row
+            = (pos->row
+               - scrollback_end
+               + term->grid->num_rows) & (term->grid->num_rows - 1);
+
+        if (_row < view_start || _row > view_end) {
+            wl_surface_attach(surf, NULL, 0, 0);
+            wl_surface_commit(surf);
+            continue;
+        }
+
         size_t text_len = wcslen(text);
         size_t chars = wcslen(key) + (text_len > 0 ? 3 + text_len : 0);
 
@@ -2562,9 +2583,14 @@ render_urls(struct terminal *term)
         struct buffer *buf = shm_get_buffer(
             term->wl->shm, width, height, shm_cookie_url(url), false, 1);
 
-        const struct coord *pos = &url->start;
-        int x = pos->col * term->cell_width - 15 * term->cell_width / 10;
-        int y = pos->row * term->cell_height - 5 * term->cell_height / 10;
+        int col = pos->col;
+        int row = pos->row - term->grid->view;
+        while (row < 0)
+            row += term->grid->num_rows;
+        row &= (term->grid->num_rows - 1);
+
+        int x = col * term->cell_width - 15 * term->cell_width / 10;
+        int y = row * term->cell_height - 5 * term->cell_height / 10;
 
         if (x < 0)
             x = 0;

url-mode.c

@@ -294,6 +294,9 @@ auto_detected(struct terminal *term, enum url_action action)
 
                     url[len] = L'\0';
 
+                    start.row += term->grid->view;
+                    end.row += term->grid->view;
+
                     tll_push_back(
                         term->urls,
                         ((struct url){